Single lever controlled geometric writing instrument

ABSTRACT

A geometric writing instrument controlled by the operation of a single lever which is used to positively draw lines and/or dots on a surface. Actuation of the single lever results in the lowering of a writing head to engage the surface. Depending upon the amount of depression of the lever, either a dot or line may be drawn perpendicular to an alignment guide. To insure a constant pressure on the writing surface, the writing head may be floatably mounted.

[ June 3, 1975 United States Patent [191 Zang 2,081,439 5/1937 Simmons...........................,. 33/39 B 3,650,612 3/1972 MZtCRlCWlCZ 33/l8 R Inventor: Eugene E. Zang, Centerville, Va. Primary Examiner Harry N. Haroian Assignee: The United States of America as Attorney, g FirmTh0m9-5 Zack; Gefsten represented by the Secretary of the ky Interior, Washington, DC.

June 21, 1974 1 SINGLE LEVER CONTROLLED [57] ABSTRACT A geometric writing instrument controlled by the operation of a single lever which is used to positively draw lines and/or dots on a surface. Actuation of the single lever results in the lowering of a writing head to 22 Filed:

21 Appl. No.: 481,719

engage the surface. Depending upon the amount of depression of the lever, either a dot or line may be 0B m9 1 3 N 33 49 "B mmoo mun ""3 m3 N h I c .r u a e m S f. C mk UIF m ned 555 drawn perpendicular to an alignment guide. To insure a constant pressure on the writing surface, the writing head may be floatably mounted.

References Cited UNITED STATES PATENTS 1,934,969 Copp 33/110 10 Claims, 6 Drawing Figures 1 SINGLE LEVER CONTROLLED GEOMETRIC WRITING INSTRUMENT BACKGROUND OF THE INVENTION 1. Field of the Invention This invention is a geometric instrument capable of drawing either a dot or a solid line perpendicular to a given guideline.

2. Description of the Prior Art Geometric instruments have long been used for drawing both negatively and positively on surfaces. In some of these instruments the writing surface is engaged by the writing instrument by placing a downward pressure upon some type of lever such as shown in the Koenig US. Pat. No. 2,902,760. In some applications, especially in cartographics, it is necessary to positively dash or dot a negatively scribed line.

It has been common practice to do such positively dashing or dotting by hand. My invention is an attempt to alleviate this burdensome chore by providing a compact, inexpensive geometric instrument that will positively draw dashes or dots perpendicular to a guiding line or other indicia whether it be negatively or positively drawn upon a surface.

SUMMARY OF THE INVENTION My invention is a geometric instrument that can draw a line and/or dot on a writing surface by means of a single lever. It consists of four basic assemblies including a mounting frame, a control assembly, an alignment guide, and the particular writing instrument used. The control assembly has a rod actuated by a lever that in turn is connected to the particular writing instrument used. Once, aligned without further movement of the instrument, by depressing the lever the writing instrument can engage the writing surface to draw a dot and if further depressed, can cause the dot to be elongated into a line on the same surface. In this way the surface may have either a dot or a line placed upon it depending upon the amount of pressure placed on the lever of the control assembly.

The principal object of this invention is an improved geometric instrument which can draw either a dot and- /or line upon the surface by actuating a single lever.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 shows a perspective view of my invention with a casing shown in dotted lines around it.

FIG. 2 shows a side view of the writing and control mechanism before actuation.

FIG. 3 shows the same side view as FIG. 2 of the writing and control mechanism upon actuation when engaging the writing surface.

FIG. 4a is a partial cross sectional view of FIG. 2 when viewed along lines 40 in the direction of the arrow.

FIG. 4b is a partial cross sectional view of FIG. 3 when viewed from the line 4b in the direction of the arrows.

FIG. 4a is a partial cross sectional view when viewed from the same direction as FIG. 4b except that the lever has been depressed to its fullest extent.

The basic components of my invention are shown in FIG. 1. Generally they may be divided into four broad categories namely: the mounting frame 11; the control assembly for the writing instrument; the alignment guide 27; and the writing instrument 15. The control assembly has a flexible elongated radius rod 13, rigidly fixed to a mount 12 which is rigidly held on frame 11. The internal rigidity of the rod causes it to be normally elevated from the frame upper surface. The other end of the radius rod extends through a writing lever mount 17 and its two parallel walls to where it terminates at its front end by engaging a writing head 14. The control assembly also has a writing lever 19 to engage the rod. This lever is attached to a shaft 18 that is generally parallel to rod 13 and is rigidly fixed within the frame mount 17. On shaft 18 two coil springs, one on either side of the lever, maintain the lever in its proper longitudinal shaft position. The frame mount 17 has a stroke guide 20 comprising two basic components. These components, best shown in FIG. 4a through 40, consists of two solid rectangular blocks held to the frame in a fixed position.

Attached to the bottom of the frame 11 and extending outward therefrom is an alignment guide 27 that allows a user to visually align the writing instrument with external surface reference indicia whether this reference indicia be negatively scribed or positively drawn on the writing surface. This guide has an alignment guide edge 22, a spacing guide edge 25, and a spacing line 26 that is used as an additional spacing guide and is parallel to edge 25. The actual writing instrument usued in my preferred embodiment was a Leroy pen which is mounted in a hole of the writing head 14.

Leroy pens per se are well known to those familiar with the geometrical instruments art. Usually they are rigidly fixed to some type of mount attached to the instrument. However, in my instrument the only thing which holds the pen is its mounting in head hole 16 which combined with the force of gravity causes the pen to assume an upright position. After ink is placed in the pens cylindrical reservoir 9 it may be dispersed through an internal conduit to its point 10 aided by this floating connection of the pen. This type of connection allows the pen toeasily move upward in its mounting hole as its writing point 10 engages the writing surface. Without such a floating mount too much pressure might be exerted on the surface by the point causing it to scratch the surface rather than draw with the constant pressure I obtain.

To prevent the pen from falling out of its mounting hole when tipped upside down a flattened cantilevered surface 28 directly above the top of the pen is used as a guard. This guard is held to the main body of the head by a screw 8 (FIGS. 1-3) that can be loosened to allow the guard to be rotated to one side so that the pen can be removed. Normally during the use of the instrument this guard never touches the top of the pen even when the pen point is pressed against the writing surface.

Additional features disclosed in FIG. 1 are: the four corner feet 24 (only 2 of which are shown) on the bottom of the frame; and the adjustment stroke screw 21 that is screwed into stroke guide 20 and acts to move radius rod 13 sidewise between the guide walls when it is engaged by the end of the screw.

FIG. 2 shows the lever 19 in its normal state before downward pressure is exerted or its upper surface by an operator. In this state the inking point 10 is elevated from the writing surface and no marks are placed thereon. FIG. 3 shown the same lever upon depression. As is apparent, the pen l5 and its attached inking head 14 have been lowered into a writing position on the surface as the rod 13 is depressed by lever 19.

The three FIGS. 4a, 4b, and 40, show the time sequence of events as an operator applies a downward force in the direction of arrow F to lever 19 with his thumb. Only the lever with its fixed shaft 18 upon which it rotates counterclockwise, the guide plate 20 (see FIG. 1) shown in cross section, and the cross section of radius rod 13 are illustrated. The two rectangular upright walls 31 and 32 are the cross-sectional views of plate 20 between which the rod extends. Although not shown by these figures, inking head 14 follows the same path as rod 13 because of its rigid attachment thereto.

In FIG. 4a a partial cross-sectional view of FIG. 2 is shown as viewed in the direction of the arrows 4a, This view shows the position of radius rod 13 prior to actuation by a user and how his rod rests upon lower camming surface 29 of the lever. FIG. 4b shows the position of rod 13 when force F is initially applied and how the rod engages the upper horizontal surface 33 of plate 20. This would result in a dot being applied to the writing surface by the pen. When further greater force F is exerted on the upper surface of lever 19, the radius rod 13 moves to the right as shown in FIG. 40 until it reaches the cut out section 30 of camming surface 29. As it moves from the left to right, as shown in FIG. 4b and 40, a solid line is being drawn upon the writing surface by the floating pen point that moves in unison with rod 13 and head 14. Thus, an operator may in one motion first, place a dot upon a written surface as in FIG. 5b and then, if he desires, by applying more force cause this dot to elongate itself into a solid continuous line.

There are three basic adjustment which can be made to change the drawing functions of this instrument. The first basic function which would change the length of the line drawn upon the surface would be to adjust the screw stroke adjustment 21 in its stroke guide and thereby change the sidewise movement of radius rod 13 between the walls 31 and 32. The next adjustment would consist of merely changing the point of the Leroy pen and thereby changing the width of the line or the diameter of the dot drawn upon the surface. The last adjustment, which is done by screws (not shown) on the under surface of frame 11 attached to guide 27, would allow the guide to be moved in and out in the lengthwise direction relative to the frame number 11.

It should thus be apparent that my instrument seeks to draw a series of dots and/or lines upon a surface when it engages the same. It can do this depending upon the amount of force applied when depressing lever 19. The writing instrument could draw a line or dot upon the surface, by a great variety of writing instruments, by changing the type of writing or scribing point used, however, the primary use I put my invention to has been to positively draw a line upon a negatively scribed surface. This particular use is very important in the map making art, especially when dotted lines such as used to designate boundaries, are needed. It should be recognized that the scope of my invention is much broader since it allows an-indiviclual guiding on a particular line (or other indicia), whether it be straight or curved, to draw not only individual lines or dots on the surface but also to draw a series of parallel lines at regular intervals or dots at regular intervals rel- 6 ment in your hand and place it so that the guide edge 22 or edge 34 is aligned with a surface reference line or other reference indicia to give a Y coordinate. The extension of edge 34, straight marker line 35, may also be used for this purpose. The particular guide edge or line chosen would depend on where it is desired to start the drawing operation. Next, either the guide spacing edge 25 or its parallel spacing line 26 is selected (X coordinate) as the distance desired between parallel dots and/or lines to be drawn on the surface having the reference line. Thus if edge 25 is selected, a shorter distance will appear than if line 26 on guide 27 were selected as the distance actually drawn is measured between where the point 10 of the pen 15 touches the surface and the selected guide.

Once the distances for guiding X and Y coordinates are selected and visually aligned with the surface indicia on which drawing is to take place, the lever 19 is depressed to place ink on the surface as the pen point impacts. Further depression results, as described with respect to FIGS. 4a-4c, in the pen point taking a L shaped trajectory, i.e. down and then to the right. Once pressure is released from lever 19, the pen point reverses its path to move from right to left and then upwards off the writing surface.

Clearly the guide distances can be varied or enlarged so that variations in spacing can be obtained. For example, several more lines parallel to line 26 could be placed on the guide 27 depending on the spacing desired between parallel lines or dots. If the thickness of the line drawn is to be varied, a new Leroy pen can be used. Also, the length of the line drawn can be varied by turning screw 21 to restrict and/or enlarge the distance rod 13 can move between restraining walls 31 and 32.

The particular materials of which this invention may be made can be varied. In one embodiment I have constructed the frame and the different mounts of a strong metallic material, the only members being constructed of a nylon organic material being the lever 19 and the feet 24.

Other variations in the particular construction of this invention are easily accomplished. None should be used to limit the scope of this invention which is set forth only in the claims that follow.

I claim:

1. A geometric instrument comprising:

a mounting frame;

a control assembly for a writing instrument rigidly attached to said frame;

a writing instrument movable by said control assembly;

a writing alignment guide with a straight edge attached to said frame and extending outward therefrom; and

means in said control assembly for moving said writing instrument to engage a writing surface to cause a dot to be formed thereon, and by further action of said means, cause said writing instrument to be moved generally perpendicular to said alignment guide straight edge to form a solid line from said dot without moving said frame on the surface.

2. The instrument of claim 1 wherein said means in said control assembly comprises a rod, and a lever with said lever having a camming surface to engage said rod.

3. The instrument of claim 1 wherein said writing instrument is mounted on a head whose movement is controlled by said control assembly to allow said writing instrument to engage the writing surface in a downward direction.

4. The instrument of claim 1 wherein said guide is rigidly attached to the under surface of the frame mounting and extends therefrom and consists of at least two edges to visually guide a user in writing upon the writing surface.

5. The instrument of claim 1 including means for floatably mounting said writing instrument to said control assembly such that a generally constant pressure is applied to the writing surface when engaged.

6. The instrument of claim 1 wherein said guide has means capable of allowing aligning of said writing instrument with a surface indicia reference whereby a regularly spaced interval may be placed between successively drawn dots and/or lines on the writing surface by moving said frame.

7. A geometric instrument comprising a frame member;

a control assembly for a writing instrument mounted on said frame having an elongated flexible rod, lever, and a camming surface on said lever to engage 6 said rod;

a writing instrument movable with the front end of said rod and normally held off a writing surface; said writing instrument having a floating mount relative to said front end of said rod and a writing alignment guide fixed to said frame member near said writing instrument.

8. The instrument of claim 7 wherein said lever is mounted to said frame member by a shaft and is capable of rotating upon said-shaft and upon depressing to engage said rod and thereby move said writing instrument towards the surface.

9. The instrument of claim 7 wherein said camming surface can move said rod and its attached writing instrument downward and then to one side depending on the amount of force exerted on the lever.

10. The instrument of claim 7 wherein said guide has means capable of allowing aligning of said writing instrument with a surface indicia reference whereby a regularly spaced interval may be placed between successively drawn dots and/or lines on the writing surface by moving said frame. 

1. A geometric instrument comprising: a mounting frame; a control assembly for a writing instrument rigidly attached to said frame; a writing instrument movable by said control assembly; a writing alignment guide with a straight edge attached to said frame and extending outward therefrom; and means in said control assembly for moving said writing instrument to engage a writing surface to cause a dot to be formed thereon, and by further action of said means, cause said writing instrument to be moved generally perpendicular to said alignment guide straight edge to form a solid line from said dot without moving said frame on the surface.
 1. A geometric instrument comprising: a mounting frame; a control assembly for a writing instrument rigidly attached to said frame; a writing instrument movable by said control assembly; a writing alignment guide with a straight edge attached to said frame and extending outward therefrom; and means in said control assembly for moving said writing instrument to engage a writing surface to cause a dot to be formed thereon, and by further action of said means, cause said writing instrument to be moved generally perpendicular to said alignment guide straight edge to form a solid line from said dot without moving said frame on the surface.
 2. The instrument of claim 1 wherein said means in said control assembly comprises a rod, and a lever with said lever having a camming surface to engage said rod.
 3. The instrument of claim 1 wherein said writing instrument is mounted on a head whose movement is controlled by said control assembly to allow said writing instrument to engage the writing surface in a downward direction.
 4. The instrument of claim 1 wherein said guide is rigidly attached to the under surface of the frame mounting and extends therefrom and consists of at least two edges to visually guide a user in writing upon the writing surface.
 5. The instrument of claim 1 including means for floatably mounting said writing instrument to said control assembly such that a generally constant pressure is applied to the writing surface when engaged.
 6. The instrument of claim 1 wherein said guide has means capable of allowing aligning of said writing instrument with a surface indicia reference whereby a regularly spaced interval may be placed between successively drawn dots and/or lines on the writing surface by moving said frame.
 7. A geometric instrument comprising a frame member; a control assembly for a writing instrument mounted on said frame having an elongated flexible rod, lever, and a camming surface on said lever to engage said rod; a writing instrument movable with the front end of said rod and normally held off a writing surface; said writing instrument having a floating mount relative to said front end of said rod and a writing alignment guide fixed to said frame member near said writing instrument.
 8. The instrument of claim 7 wherein said lever is mounted to said frame member by a Shaft and is capable of rotating upon said shaft and upon depressing to engage said rod and thereby move said writing instrument towards the surface.
 9. The instrument of claim 7 wherein said camming surface can move said rod and its attached writing instrument downward and then to one side depending on the amount of force exerted on the lever. 